Square Speed/Fuel Gauge replaced now need help

[Capt.Terry]

Hi, I need some help on this please, I have installed a replacement "Speed Fuel" Yamaha gauge.How does this new replacement gauge know what size the fuel tank is my boat? if I do not tell it? this gauge is a Square Multi link gauge, it is set for the asbyc(us) fuel sensor unit. This gauge is not a fuel only gauge, as that gauge can be set for tank capacity. So how can it tell me how much fuel is remaining if it doesn't know my size tank? Can anyone advise me. The boat is new to me, and the fuel tank has now been filled to the top. I Need to know what to do. I have reset the TTL to zero. Holding down the mode and set buttons for one second. I have read the .pdf manuals on these gauges but nothing tells me if it is automatic. This gauge does not have the feature, to set Tank capacity?

[boscoe99]

Speaking from a tired and failing memory, I don't think you can tell the square Speed Fuel gauge the tank size. This is only done with the square standalone Fuel (Management) gauge.

[rodbolt17]

best I recall it is used only with command link plus.

[fairdeal]

I have reset the TTL to zero. Holding down the mode and set buttons for one second.

I was interested to see that the fuel level display on that gauge apparently has a "resolution" of 20 steps - or ~5%.

But seems clear that as Boscoe says, it is up to the owner to do the mental match to convert that to gallons,

as it is only a graphical representation of the signal from the tank sender.

(also interesting that the setup procedure utilizes those fuel level "bars" to identify the particular "display configuration" selected)

[boscoe99]

The square fuel gauge allows the user to enter the capacity of the fuel tank. The gauge will then show 90% of the fuel tank capacity as being available. There is a 10% reserve factor built in.

As fuel used is provided to the gauge by the motor the gauge will subtract that amount from the initial value to indicate fuel remaining. Le'ts say a 100 gallon tank. Gauge will initially show 90 gallons as being available. Engine tells the gauge that 20 gallons have been burned. Gauge will show 20 gallons as being used. Gauge will show 70 gallons (90 minus 20) as being available.

Tank gets filled up, gauge is reset by the owner, and the process starts over.

The combination speed fuel gauge does not have the same capability that the standalone fuel gauge has. It is a trade off. One gauge type has certain functions that the other gauge type does not have and vice versa.

As fairwinds notes, with the speed fuel (combo) gauge it will tell the user how much has been used. It is up to the user to mentally subtract the fuel used amount from the tank amount. Or a calculator can be used if one wants.

[rodbolt17]

my seapro fuel gauge sender is wrong, it will only stop dropping the bars on the speed/fuel meter when it goes below 18 gallons.
I would fix it but I am to lazy to remove the second station ladder.

however when I fill it I 0 the meter.
I know it holds 65 gallons and when the bars start dropping it is lower than 18 gallons.
with a fuel burn rate of 6GPH at 30 mph it is not hard to figure out I have a max of about 90 miles or about 3 more hours.

[Capt.Terry]

OK, so I am hunting for an answer that is not available,
this "Speed Fuel" Gauge can and only tells me the fuel burned! I do the math now, that I know the tank is full, I'll have to keep a log. Reading the manual was confusing with programming as the fuel only gauge has this option of tank size, one would think the multi gauge would still have that available?
Thank you all for the responses...

[fairdeal]

The Command Link instruments seem to be very nicely engineered,

but the manuals are - IMO - a travesty.

sometimes even when I know what they are "trying to say",

what they've actually said is incomprehensible...such as

[boscoe99]

OK, so I am hunting for an answer that is not available,
this "Speed Fuel" Gauge can and only tells me the fuel burned! I do the math now, that I know the tank is full, I'll have to keep a log. Reading the manual was confusing with programming as the fuel only gauge has this option of tank size, one would think the multi gauge would still have that available?
Thank you all for the responses...

With Yamaha, it ain't necessarily so. Who knows what (or if) they are doing much thinking at all.

[donsmarine]

go to yamaha home page, go to rigging, go to gauges, manuals are at bottom of scroll down, maybe this will help